1. Field of the Invention
This invention relates generally to electromagnetic interference (EMI) shields, and more specifically relates to pouches and tents for use in shielding electronics from EMI and wireless communication signals.
2. Description of Related Art
It is well known that electromagnetic signals propagate through vacuum with little signal attenuation. It is also well known that electromagnetic radiation and signals attenuate when propagating through materials other than a vacuum. Electromagnetic signals rapidly attenuate in metal materials. For this reason, metal housings are commonly used to hold electronic equipment in order to minimize EMI caused by the electronics associated with the electronic equipment when operating. While metal housing are useful for shielding electronic objects, they are generally bulky, heavy, non-portable and not suitable for containing arbitrarily sized electronic objects.
U.S. Pat. No. 5,791,485 to Carbonneau discloses an electrostatic discharge protection bag that included a multilayer film with metalization sandwiched between antistatic films that is designed to protect an electronic circuit card or module from electrostatic discharge and has some limited EMI attenuation. The metalized layer used in the Carbonneau bag is available from Metalization Products, Winchester, Mass. The Carbonneau bag also includes a layer of bubble pack cushioning material for mechanical protection of the circuit card.
U.S. Patent Application Publication No. US 2005/0118366 to Piemonte et al. discloses containers made barrier materials. External layers of the Piemonte et al. container may include Aluminum and Copper metallization layers on a polymer substrate for EMI shielding. The Piemonte et al. container also includes a vapor barrier layer sandwiched between the external metallization layers to resist transmission of O2, H2O and CO2 or any other vapor desired to be blocked.
U.S. Pat. No. 6,140,576 to Kanne et al. discloses a portable tent structure for protecting electronic assemblies during various stages of a manufacturing process. The Kanne et al. tent includes a collapsible frame for supporting a protective covering that creates an EMI shield around the object inside the tent. The protective covering of the Kanne et al. tent includes a foil layer and a carrier layer, e.g., polyester that may be fabricated as cloth interwoven with various metallic threads.
An EMI shield would also be useful when gathering electronic forensic evidence. For example, when a portable wireless device is initially seized from its owner, it is important to ensure that proper wireless procedures are maintained and that the evidence is protected from potential mistakes that destroy the validity or credibility of the evidence, particularly from after seizure wireless communications. Thus, there is a need in the art for a container for storing a portable wireless device and yet that would allow controlled extraction of the data on the portable wireless device without allowing EMI to corrupt the data or evidence in the portable wireless device.
The Carbonneau and Piemonte et al. containers are not designed to provide for external connection to evidence gathering devices while shielding the portable wireless device containing the evidence of interest. Furthermore, the Carbonneau bag includes a layer of bubble pack cushioning material for mechanical protection of electrical object inside which is generally unnecessary in the forensic evidence gathering context and adds cost to the EMI container. Similarly, the Piemonte et al. container includes an unnecessary vapor barrier layer that ads cost.
The Kanne et al. tents are sized to protect satellites and other bulky electronic objects. But, it would be desirable to have an EMI shield that would completely contain a user seated with forensic data extraction equipment connected to the electronic device of interest during evidence extraction, that includes a floor and that provides a means of ingress and egress to and from the inside of the EMI shield tent and methods of using same, to extract the forensic evidence, i.e., data.
Thus, there exists a need in the art for EMI shielding containers that can be used in the context of gathering electronic data from the shielded electronic device for forensic evidence that are not disclosed in the prior art.